Method of making semiconductor device structures by means of ion implantation under a partial pressure of oxygen

摘要

Disclosed is a simplified method of producing semiconductor device structures in an integrated technology using at least one ion implantation step. Implantation of the doping ions into a silicon wafer, for example, for producing a subcollector or an emitter, is not effected, as previously, in an ultra-high vacuum atmosphere through a thin protective layer of silicon dioxide which is applied by a separate thermal oxidation step prior to implantation, but the doping ions are directly implanted into the bare silicon wafer. The latter implantation is effected in an atmosphere of increased partial pressure of oxygen. Enhanced diffusion of the oxygen adsorbed at the surface occurs into the vacancies which are generated by the implanted doping ions close the surface of the silicon wafer. In this manner a silicon dioxide protective layer is formed already in the initial stage of ion implantation. As a result one process step can be saved, namely, the production of the protective layer by thermal oxidation prior to ion implantation.